title: An efficient, thermally stable cerium-based silicate phosphor for solid state white lighting.
abstract: A novel cerium-substituted, barium yttrium silicate has been identified as an efficient blue-green phosphor for application in solid state lighting. Ba9Y2Si6O24:Ce(3+) was prepared and structurally characterized using synchrotron X-ray powder diffraction. The photoluminescent characterization identified a major peak at 394 nm in the excitation spectrum, making this material viable for near-UV LED excitation. An efficient emission, with a quantum yield of ≈60%, covers a broad portion (430-675 nm) of the visible spectrum, leading to the blue-green color. Concentration quenching occurs when the Ce(3+) content exceeds ≈3 mol %, whereas high temperature photoluminescent measurements show a 25% drop from the room temperature efficiency at 500 K. The emission of this compound can be red-shifted via the solid solution Ba9(Y(1-y)Sc(y))(1.94)Ce(0.06)Si6O24 (y = 0.1, 0.2), allowing for tunable color properties when device integration is considered.
authors.affiliation: Solid State Lighting and Energy Center, University of California, Santa Barbara, Santa Barbara, California 93106, USA. jrbrgoch@mrl.ucsb.edu
authors.forename: Jakoah
authors.initials: J
authors.lastname: Brgoch
authors.forename: Christopher K H
authors.initials: CK
authors.lastname: Borg
authors.forename: Kristin A
authors.initials: KA
authors.lastname: Denault
authors.forename: Alexander
authors.initials: A
authors.lastname: Mikhailovsky
authors.forename: Steven P
authors.initials: SP
authors.lastname: DenBaars
authors.forename: Ram
authors.initials: R
authors.lastname: Seshadri